JP2010031228A - Cellulose derivative, resin composition, molded article, and housing for electrical/electronic apparatus - Google Patents

Abstract

To provide a cellulose derivative and a resin composition having good thermoplasticity, strength and heat resistance and suitable for molding processing.
A cellulose derivative in which at least a part of hydrogen atoms of a hydroxyl group contained in cellulose is substituted with a hydrocarbon group having 1 to 7 carbon atoms and an aliphatic acyl group having 4 to 11 carbon atoms.
[Selection figure] None

Description

  The present invention relates to a novel cellulose derivative, a resin composition, a molded body, and a casing for an electric / electronic device.

  Various materials are used for members constituting electric and electronic devices such as copiers and printers in consideration of characteristics and functions required for the members. For example, the members (cases) that store the drive units of electrical and electronic equipment and protect the drive units are generally PC (Polycarbonate), ABS (Acrylonitrile-butadiene-styrene) resin, PC / ABS, etc. In large amounts (Patent Document 1). These resins are produced by reacting compounds obtained from petroleum as a raw material.

  By the way, fossil resources such as oil, coal, and natural gas are mainly composed of carbon that has been fixed in the ground for many years. When such fossil resources or products made from fossil resources are burned and carbon dioxide is released into the atmosphere, carbon that was originally not deep in the atmosphere but fixed deep in the ground Is rapidly released as carbon dioxide, and carbon dioxide in the atmosphere greatly increases, which causes global warming. Therefore, polymers such as ABS and PC made from petroleum, which is a fossil resource, have excellent characteristics as materials for components for electric and electronic equipment, but are made from petroleum, which is a fossil resource. Therefore, from the viewpoint of preventing global warming, it is desirable to reduce the amount used.

On the other hand, a plant-derived resin is originally produced by a photosynthesis reaction using carbon dioxide and water in the atmosphere as raw materials. Therefore, even if plant-derived resin is incinerated to generate carbon dioxide, the carbon dioxide is equivalent to carbon dioxide originally in the atmosphere, so the balance of carbon dioxide in the atmosphere is plus or minus zero After all, there is an idea that the total amount of CO _{2 in} the atmosphere is not increased. Based on this idea, plant-derived resins are referred to as so-called “carbon neutral” materials. The use of carbon-neutral materials in place of petroleum-derived resins is an urgent need to prevent global warming in recent years.

  For this reason, in PC polymer, the method of reducing petroleum origin resources is proposed by using plant origin resources, such as starch, as some raw materials derived from petroleum (patent documents 2). However, further improvements are required from the perspective of aiming for a more complete carbon neutral material.

JP-A-56-55425 JP 2008-24919 A

The present inventors paid attention for the first time to use cellulose as a carbon neutral resin. However, since cellulose generally does not have thermoplasticity, it is difficult to mold by heating or the like, and thus is not suitable for molding. Further, even if thermoplasticity can be imparted, there is a problem that strength such as impact resistance is greatly reduced. Furthermore, there is room for improvement in terms of heat resistance.
An object of the present invention is to provide a cellulose derivative and a resin composition which have good thermoplasticity, strength and heat resistance and are suitable for molding processing.

The present inventors pay attention to the molecular structure of cellulose, and find that the cellulose has a specific structure to produce good thermoplasticity, impact resistance and heat resistance, and complete the present invention. It came to.
That is, the said subject can be achieved by the following means.
1. A cellulose derivative in which at least part of hydrogen atoms of a hydroxyl group contained in cellulose is substituted with a hydrocarbon group having 1 to 7 carbon atoms and an aliphatic acyl group having 4 to 11 carbon atoms.
2. 2. The cellulose derivative according to 1 above, wherein the aliphatic acyl group has a branched structure.
3. The cellulose derivative according to 1 or 2 above, wherein the aliphatic acyl group has 7 to 9 carbon atoms.
4). The cellulose derivative according to any one of the above 1 to 3, wherein the hydrocarbon group is a methyl group or an ethyl group.
5). The cellulose derivative according to any one of 1 to 3, wherein the hydrocarbon group is a methyl group.
6). The resin composition containing the cellulose derivative in any one of said 1-5.
7). A molded product obtained by molding the cellulose derivative according to any one of 1 to 5 or the resin composition according to 6 above.
8). A casing for an electric / electronic device comprising the molded article according to 7 above.
9. 6. A method for producing a cellulose derivative according to any one of 1 to 5, which comprises a step of reacting cellulose ether with an acid chloride or an acid anhydride in the presence of a base.

  Since the cellulose derivative or resin composition of the present invention has excellent thermoplasticity, it can be formed into a molded body. In addition, the molded body formed of the cellulose derivative or resin composition of the present invention has good impact resistance, heat resistance, etc., components such as automobiles, home appliances, electric / electronic devices, mechanical parts, It can be suitably used as a house / building material. Moreover, since it is a plant-derived resin, it can be replaced with a conventional petroleum-derived resin as a material that can contribute to the prevention of global warming.

Hereinafter, the present invention will be described in detail.
1. Cellulose Derivative The cellulose derivative of the present invention comprises a hydrocarbon group having 1 to 7 carbon atoms and 4 to 11 carbon atoms in which at least some of the hydrogen atoms of the hydroxyl group contained in cellulose ((C ₆ H ₁₀ O ₅ ) _n ). Substituted with an aliphatic acyl group.
That is, the cellulose derivative of the present invention has a polymer unit represented by the following general formula (1).

In the above formula, R ² , R ³ and R ⁶ each independently represent a hydrogen atom, a hydrocarbon group having 1 to 7 carbon atoms, or an aliphatic acyl group having 4 to 11 carbon atoms. However, at least one of R ² , R ³ , and R ⁶ is a hydrocarbon group having 1 to 7 carbon atoms or an aliphatic acyl group having 4 to 11 carbon atoms.

  The cellulose derivative of the present invention can exhibit thermoplasticity by etherification and esterification of at least a part of the hydroxyl group of the β-glucose ring with a hydrocarbon group having a specific carbon number as described above, It is suitable for molding. Moreover, the cellulose derivative of the present invention can exhibit excellent strength and heat resistance as a molded body. Furthermore, since cellulose is a complete plant-derived component, it is carbon neutral and can greatly reduce the burden on the environment.

The “cellulose” referred to in the present invention is a polymer compound in which a large number of glucoses are polymerized by β-1,4-glycosidic bonds, and the carbon atoms at the 2nd, 3rd and 6th positions in the glucose ring of cellulose. Means that the hydroxyl group bonded to is unsubstituted.
Further, “hydroxyl group contained in cellulose” refers to a hydroxyl group bonded to carbon atoms at the 2nd, 3rd and 6th positions in the glucose ring of cellulose.

The cellulose derivative of the present invention only needs to contain the hydrocarbon group and aliphatic acyl group having the specific carbon number in any part of the whole, and may be composed of the same polymerization unit, It may consist of the following types of polymerized units. Moreover, the cellulose derivative of the present invention does not need to contain both the hydrocarbon group and the aliphatic acyl group in one polymerization unit.
For example, (1) a monomer in which a part of R ² , R ³ and R ⁶ is substituted with a hydrocarbon group, and a part of R ² , R ³ and R ⁶ are substituted with an aliphatic acyl group (2) a single polymer unit in which R ² , R ³ and R ⁶ are both substituted with a hydrocarbon group and an aliphatic acyl group. A polymer composed of one monomer may be used. Further, (3) a polymer in which different types of polymer units represented by the general formula (1) are randomly polymerized may be used.
In addition, a part of the polymer may contain an unsubstituted polymer unit (that is, a polymer unit in which R ² , R ^3, and R ⁶ are all hydrogen atoms in the general formula (1)).

The hydrocarbon group having 1 to 7 carbon atoms may be either an aliphatic group or an aromatic group. In the case of an aliphatic group, it may be linear, branched or cyclic, and may have an unsaturated bond. Preferably it is a C1-C4 aliphatic group.
Specific examples include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, pentyl group, hexyl group, heptyl group and the like. A methyl group or an ethyl group is preferable, and a methyl group is more preferable. These may be used alone or in a combination of two or more.

The aliphatic acyl group having 4 to 11 carbon atoms preferably has 7 to 9 carbon atoms, and more preferably 8 carbon atoms.
Specifically, butyryl group, isobutyryl group, pentanoyl group, 2-methylbutanoyl group, 3-methylbutanoyl group, pivaloyl group, hexanoyl group, 2-methylpentanoyl group, 3-methylpentanoyl group, 4- Methylpentanoyl group, 2,2-dimethylbutanoyl group, 2,3-dimethylbutanoyl group, 3,3-dimethylbutanoyl group, 2-ethylbutanoyl group, heptanoyl group, 2-methylhexanoyl group, 3 -Methylhexanoyl group, 4-methylhexanoyl group, 5-methylhexanoyl group, 2,2-dimethylpentanoyl group, 2,3-dimethylpentanoyl group, 3,3-dimethylpentanoyl group, 2-ethyl Pentanoyl group, cyclohexanoyl group, octanoyl group, 2-methylheptanoyl group, 3-methylheptanoyl group, 4-methyl Heptanoyl group, 5-methylheptanoyl group, 6-methylheptanoyl group, 2,2-dimethylhexanoyl group, 2,3-dimethylhexanoyl group, 3,3-dimethylhexanoyl group, 2-ethylhexanoyl group 2-propylpentanoyl group, nonanoyl group, 2-methyloctanoyl group, 3-methyloctanoyl group, 4-methyloctanoyl group, 5-methyloctanoyl group, 6-methyloctanoyl group, 2,2- Dimethylheptanoyl group, 2,3-dimethylheptanoyl group, 3,3-dimethylheptanoyl group, 2-ethylheptanoyl group, 2-propylhexanoyl group, 2-butylpentanoyl group, decanoyl group, 2-methylnonanoyl Group, 3-methylnonanoyl group, 4-methylnonanoyl group, 5-methylnonanoyl group, 6-methylnonanoyl group Group, 7-methylnonanoyl group, 2,2-dimethyloctanoyl group, 2,3-dimethyloctanoyl group, 3,3-dimethyloctanoyl group, 2-ethyloctanoyl group, 2-propylheptanoyl group, 2 -A butylhexanoyl group, 2-propyloctanoyl group, etc. are mentioned. These may be used alone or in a combination of two or more.

The aliphatic moiety of the aliphatic acyl group having 4 to 11 carbon atoms may have any of a straight chain structure, a branched structure, and a cyclic structure, but preferably has a branched structure, in particular, the α-position of the carbonyl group An aliphatic moiety having a branched structure is more preferred. Thereby, strength, such as impact resistance, can be improved.
As the aliphatic acyl group having a branched aliphatic moiety, a 2-propylpentanoyl group, a 2-ethylhexanoyl group, a 2-methylheptanoyl group, and the like are particularly preferable.

The aliphatic acyl group may have a further substituent. Further substituents include, for example, a hydroxy group, a mercapto group, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), a cyano group, a sulfo group, a carboxyl group, a nitro group, a hydroxamic acid group, a sulfino group, A hydrazino group, an imino group, etc. are mentioned.
When the aliphatic acyl group has a further substituent and the substituent includes carbon, the carbon number of the substituent is not included as the carbon number of the aliphatic acyl group.

The substitution position of the hydrocarbon group and the aliphatic acyl group in the cellulose derivative, and the number (substitution degree) of the hydrocarbon group and the aliphatic acyl group per β-glucose ring unit are not particularly limited.
For example, the substitution degree DS _B of the hydrocarbon group (the number of hydrocarbon groups relative to the hydroxyl groups at the 2nd, 3rd and 6th positions of the β-glucose ring in the polymer unit) is usually about 1.0 or more, preferably 1. What is necessary is just about 5-2.5.
Substitution degree DS _C of aliphatic acyl group (number of aliphatic acyl groups relative to hydroxyl groups at positions 2, 3 and 6 of the cellulose structure of the β-glucose ring in the polymerization unit) is usually about 0.1 or more, preferably What is necessary is just to be about 0.3-1.5. By setting it as the substituent of such a range, heat resistance, brittleness, etc. can be improved.

Further, the number of unsubstituted hydroxyl groups present in the cellulose derivative is not particularly limited.
The substitution degree DS _{A of} hydrogen atoms (ratio in which the hydroxyl groups at the 2-position, 3-position and 6-position in the polymerization unit are unsubstituted) is usually about 0.01 to 1.5, preferably about 0.2 to 1.2. And it is sufficient. The DS _A by 0.01 or more, it is possible to improve the fluidity of the resin composition. Further, by setting the DS _A and 1.5 or less, or to improve the fluidity of the resin composition, foaming or the like due to water absorption of the resin composition during acceleration and molding of the pyrolysis can or is suppressed.
Note that the sum of the degrees of substitution (DS _A + DS _B + DS _C ) is 3.

The molecular weight of the cellulose derivative of the present invention is preferably in the range of 5,000 to 1,000,000, more preferably in the range of 10,000 to 500,000, and most preferably in the range of 100,000 to 200,000. The weight average molecular weight (Mw) is preferably in the range of 7000 to 5000000, more preferably in the range of 15000 to 2500,000, and most preferably in the range of 300000 to 150,000. The molecular weight distribution (MWD) is preferably in the range of 1.1 to 5.0, and more preferably in the range of 1.5 to 3.5. By setting the average molecular weight within this range, it is possible to improve the moldability and mechanical strength of the molded body. Moreover, moldability etc. can be improved by setting it as the molecular weight distribution of this range.
In the present invention, the number average molecular weight (Mn), weight average molecular weight (Mw) and molecular weight distribution (MWD) can be measured using gel permeation chromatography (GPC). Specifically, tetrahydrofuran can be used as a solvent, polystyrene gel can be used, and the molecular weight can be obtained using a conversion molecular weight calibration curve obtained in advance from a constituent curve of standard monodisperse polystyrene.

2. Production Method of Cellulose Derivative The production method of the cellulose derivative of the present invention is not particularly limited, and the cellulose derivative of the present invention can be produced by using cellulose as a raw material and etherifying and esterifying cellulose. The raw material for cellulose is not limited, and examples thereof include cotton, linter, and pulp.
In a preferred production method, a cellulose ether (a cellulose derivative in which at least a part of hydrogen atoms of hydroxyl groups at positions 2, 3, and 6 of the β-glucose ring is substituted with a hydrocarbon group) in the presence of a base, It includes a step of esterification by reacting acid chloride or acid anhydride.

As the cellulose ether, for example, a cellulose ether in which a hydrogen atom of a hydroxyl group contained in cellulose is substituted with an alkyl group having 1 to 7 carbon atoms is used.
Specific examples include methyl cellulose, ethyl cellulose, propyl cellulose, butyl cellulose, allyl cellulose, and benzyl cellulose.

  As the acid chloride, for example, a C 4-11 carboxylic acid chloride is used. Examples of the carboxylic acid chloride having 4 to 11 carbon atoms include butyryl chloride, isobutyryl chloride, pentanoyl chloride, 2-methylbutanoyl chloride, 3-methylbutanoyl chloride, pivaloyl chloride, hexanoyl chloride, 2-methylpentanoyl chloride, 3-methylpentanoyl chloride, 4-methylpentanoyl chloride, 2,2-dimethylbutanoyl chloride, 2,3-dimethylbutanoyl chloride, 3,3-dimethylbutanoyl chloride, 2- Ethylbutanoyl chloride, heptanoyl chloride, 2-methylhexanoyl chloride, 3-methylhexanoyl chloride, 4-methylhexanoyl chloride, 5-methylhexanoyl chloride, 2,2-dimethylpentanoyl chloride, 2,3- Dimethylpentanoyl Loride, 3,3-dimethylpentanoyl chloride, 2-ethylpentanoyl chloride, cyclohexanoyl chloride, octanoyl chloride, 2-methylheptanoyl chloride, 3-methylheptanoyl chloride, 4-methylheptanoyl chloride, 5- Methylheptanoyl chloride, 6-methylheptanoyl chloride, 2,2-dimethylhexanoyl chloride, 2,3-dimethylhexanoyl chloride, 3,3-dimethylhexanoyl chloride, 2-ethylhexanoyl chloride, 2-propylpenta Noyl chloride, nonanoyl chloride, 2-methyloctanoyl chloride, 3-methyloctanoyl chloride, 4-methyloctanoyl chloride, 5-methyloctanoyl chloride, 6-methyloctanoyl chloride, 2,2-dimethyl Ptanoyl chloride, 2,3-dimethylheptanoyl chloride, 3,3-dimethylheptanoyl chloride, 2-ethylheptanoyl chloride, 2-propylhexanoyl chloride, 2-butylpentanoyl chloride, decanoyl chloride, 2-methyl Nonanoyl chloride, 3-methylnonanoyl chloride, 4-methylnonanoyl chloride, 5-methylnonanoyl chloride, 6-methylnonanoyl chloride, 7-methylnonanoyl chloride, 2,2-dimethyloctanoyl chloride, 2, Examples include 3-dimethyloctanoyl chloride, 3,3-dimethyloctanoyl chloride, 2-ethyloctanoyl chloride, 2-propylheptanoyl chloride, 2-butylhexanoyl chloride and the like.

  As the acid anhydride, for example, a carboxylic acid anhydride composed of a carboxylic acid having 4 to 11 carbon atoms is used. Examples of such carboxylic anhydrides include butyric anhydride, valeric anhydride, hexanoic anhydride, heptanoic anhydride, octanoic anhydride, 2-ethylhexanoic anhydride, nonanoic anhydride, and the like. Can be mentioned.

  As the base, for example, pyridine, lutidine, dimethylaminopyridine, triethylamine, diethylbutylamine, diazabicycloundecene, potassium carbonate and the like can be used. Of these, pyridine, dimethylaminopyridine and the like are preferable.

  Other specific production conditions and the like can follow conventional methods. For example, a method described in “Encyclopedia of Cellulose” pages 131 to 164 (Asakura Shoten, 2000) can be referred to.

3. Resin composition containing cellulose derivative and molded article The resin composition of the present invention contains the cellulose derivative of the present invention, and may contain other additives as necessary.
The content ratio of the components contained in the resin composition is not particularly limited. The cellulose derivative is about 75% by mass or more, preferably about 80% by mass or more, and more preferably about 80 to 100% by mass.
In addition to the cellulose derivative of the present invention, the resin composition of the present invention may contain various additives such as a filler and a flame retardant as necessary.

  The resin composition of the present invention may contain a filler (reinforcing material). By containing the filler, the mechanical properties of the molded body formed from the resin composition can be enhanced.

A well-known thing can be used as a filler. The shape of the filler may be any of fibrous, plate-like, granular, powdery and the like. Further, it may be inorganic or organic.
Specifically, as the inorganic filler, glass fiber, carbon fiber, graphite fiber, metal fiber, potassium titanate whisker, aluminum borate whisker, magnesium whisker, silicon whisker, wollastonite, sepiolite, slag fiber, zonolite, Elastadite, gypsum fiber, silica fiber, silica-alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber and boron fiber, and other inorganic fillers; glass flakes, non-swellable mica, carbon black, graphite, metal foil , Ceramic beads, talc, clay, mica, sericite, zeolite, bentonite, dolomite, kaolin, fine silica, feldspar powder, potassium titanate, shirasu balloon, calcium carbonate, magnesium carbonate, barium sulfate, calcium oxide Um, aluminum oxide, titanium oxide, magnesium oxide, aluminum silicate, silicon oxide, aluminum hydroxide, magnesium hydroxide, gypsum, novaculite, dawsonite, and a plate-like or granular inorganic fillers of clay or the like.

  Organic fillers include synthetic fibers such as polyester fiber, nylon fiber, acrylic fiber, regenerated cellulose fiber, and acetate fiber, and natural fibers such as kenaf, ramie, cotton, jute, hemp, sisal, Manila hemp, flax, linen, silk, and wool. Examples thereof include fibrous organic fillers obtained from microcrystalline cellulose, sugar cane, wood pulp, paper waste, waste paper and the like, and granular organic fillers such as organic pigments.

  When the resin composition contains a filler, the content is not limited, but is usually about 30 parts by mass or less, preferably about 5 to 10 parts by mass with respect to 100 parts by mass of the cellulose derivative.

The resin composition of the present invention may contain a flame retardant. Thereby, the flame retarding effect such as reduction or suppression of the burning rate can be improved.
The flame retardant is not particularly limited, and a conventional flame retardant can be used. For example, brominated flame retardants, chlorine-based flame retardants, phosphorus-containing flame retardants, silicon-containing flame retardants, nitrogen compound-based flame retardants, inorganic flame retardants and the like can be mentioned. Among these, hydrogen halides are not generated by thermal decomposition during compounding with resin or during molding, causing corrosion of processing machines and molds, and worsening the work environment. Phosphorus-containing flame retardants and silicon-containing flame retardants are preferred because they are less likely to adversely affect the environment through the generation of harmful substances such as dioxins when they are diffused or decomposed.

  The phosphorus-containing flame retardant is not particularly limited, and a commonly used one can be used. Examples thereof include organic phosphorus compounds such as phosphate esters, phosphate condensation esters, and polyphosphates.

  Specific examples of phosphate esters include trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri (2-ethylhexyl) phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, tris (isopropylphenyl) Phosphate, tris (phenylphenyl) phosphate, trinaphthyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, diphenyl (2-ethylhexyl) phosphate, di (isopropylphenyl) phenyl phosphate, monoisodecyl phosphate, 2-acryloyloxyethyl Acid phosphate, 2-methacryloyloxyethyl acid phosphate, diphenyl Examples include 2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate, melamine phosphate, dimelamine phosphate, melamine pyrophosphate, triphenylphosphine oxide, tricresylphosphine oxide, diphenyl methanephosphonate, diethyl phenylphosphonate be able to.

  Examples of phosphoric acid condensed esters include resorcinol polyphenyl phosphate, resorcinol poly (di-2,6-xylyl) phosphate, bisphenol A polycresyl phosphate, hydroquinone poly (2,6-xylyl) phosphate, and condensates thereof. Aromatic phosphoric acid condensed ester and the like.

  Moreover, the polyphosphate which consists of a salt of phosphoric acid, polyphosphoric acid, a periodic table group 1-14 group metal, ammonia, an aliphatic amine, and an aromatic amine can also be mentioned. As typical salts of polyphosphates, lithium salts, sodium salts, calcium salts, barium salts, iron (II) salts, iron (III) salts, aluminum salts, etc. as metal salts, methylamine salts as aliphatic amine salts, Examples include ethylamine salts, diethylamine salts, triethylamine salts, ethylenediamine salts, piperazine salts, and examples of aromatic amine salts include pyridine salts and triazines.

In addition to the above, halogen-containing phosphate esters such as trischloroethyl phosphate, trisdichloropropyl phosphate, tris (β-chloropropyl) phosphate), and structures in which a phosphorus atom and a nitrogen atom are connected by a double bond Phosphazene compounds having phosphoric acid and phosphoric ester amides.
These phosphorus-containing flame retardants may be used singly or in combination of two or more.

The silicon-containing flame retardant is represented by the formula: R _m Si _{(4-m) / 2} (m is an integer of 1 to 3, R is a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, or an aromatic carbonization. A hydrogen atom, a methyl group at the side chain or at the end of the organosilicon compound, polydimethylsiloxane, or polydimethylsiloxane having a two- or three-dimensional structure whose main structural unit is a structural unit represented by Alternatively, an unsubstituted aliphatic hydrocarbon group, an aromatic hydrocarbon group substituted or modified, a so-called silicone oil, or a modified silicone oil can be used.

Examples of the substituted or unsubstituted aliphatic hydrocarbon group and aromatic hydrocarbon group include an alkyl group, a cycloalkyl group, a phenyl group, a benzyl group, an amino group, an epoxy group, a polyether group, a carboxyl group, a mercapto group, Examples include a chloroalkyl group, an alkyl higher alcohol ester group, an alcohol group, an aralkyl group, a vinyl group, or a trifluoromethyl group.
These silicon-containing flame retardants may be used alone or in combination of two or more.

  Examples of the flame retardant other than the phosphorus-containing flame retardant or the silicon-containing flame retardant include, for example, magnesium hydroxide, aluminum hydroxide, antimony trioxide, antimony pentoxide, sodium antimonate, zinc hydroxystannate, zinc stannate, Metastannic acid, tin oxide, tin oxide salt, zinc sulfate, zinc oxide, ferrous oxide, ferric oxide, stannous oxide, stannic oxide, zinc borate, ammonium borate, ammonium octamolybdate, tungsten Inorganic flame retardants such as acid metal salts, complex oxides of tungsten and metalloid, ammonium sulfamate, ammonium bromide, zirconium compounds, guanidine compounds, fluorine compounds, graphite, and swellable graphite can be used. . These other flame retardants may be used alone or in combination of two or more.

  When the resin composition of the present invention contains a flame retardant, its content is not limited, but is usually about 30 parts by mass or less, preferably about 2 to 10 parts by mass with respect to 100 parts by mass of the cellulose derivative. Good. By setting it as this range, impact resistance, brittleness, etc. can be improved, or generation | occurrence | production of pellet blocking can be suppressed.

In addition to the cellulose derivative, filler and flame retardant, the resin composition of the present invention is not limited to the purpose of the present invention, and other properties are intended to further improve various properties such as moldability and flame retardancy. Ingredients may be included.
Examples of other components include polymers other than the cellulose derivatives, plasticizers, stabilizers (antioxidants, UV absorbers, etc.), mold release agents (fatty acids, fatty acid metal salts, oxyfatty acids, fatty acid esters, aliphatic moieties. Saponified ester, paraffin, low molecular weight polyolefin, fatty acid amide, alkylene bis fatty acid amide, aliphatic ketone, fatty acid lower alcohol ester, fatty acid polyhydric alcohol ester, fatty acid polyglycol ester, modified silicone), antistatic agent, flame retardant aid, Examples include processing aids, anti-drip agents, antibacterial agents, and antifungal agents. Furthermore, a coloring agent containing a dye or a pigment can be added.

  As the polymer other than the cellulose derivative, either a thermoplastic polymer or a thermosetting polymer can be used, but a thermoplastic polymer is preferable from the viewpoint of moldability. Specific examples of polymers other than cellulose derivatives include low density polyethylene, linear low density polyethylene, high density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-propylene-nonconjugated diene copolymer, ethylene-butene- 1 copolymer, polypropylene homopolymer, polypropylene copolymer (such as ethylene-propylene block copolymer), polyolefins such as polybutene-1 and poly-4-methylpentene-1, polybutylene terephthalate, polyethylene terephthalate and other aromatic polyesters, etc. Polyamide such as polyester, nylon 6, nylon 46, nylon 66, nylon 610, nylon 612, nylon 6T, nylon 12, etc., polystyrene, high impact polystyrene, poly Settals (including homopolymers and copolymers), polyurethanes, aromatic and aliphatic polyketones, polyphenylene sulfide, polyetheretherketone, thermoplastic starch resins, polymethyl methacrylate and methacrylate-acrylate copolymers Acrylic resin, AS resin (acrylonitrile-styrene copolymer), ABS resin, AES resin (ethylene rubber reinforced AS resin), ACS resin (chlorinated polyethylene reinforced AS resin), ASA resin (acrylic rubber reinforced AS resin) , Polyvinyl chloride, polyvinylidene chloride, vinyl ester resin, maleic anhydride-styrene copolymer, MS resin (methyl methacrylate-styrene copolymer), polycarbonate, polyarylate, polysulfone, polyethersulfone, pheno Thermoplastic polyimide such as silicone resin, polyphenylene ether, modified polyphenylene ether, polyetherimide, polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-ethylene copolymer, tetrafluoroethylene-perfluoro Fluoropolymers such as alkyl vinyl ether copolymer, polychlorotrifluoroethylene, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene-perfluoroalkyl vinyl ether copolymer, cellulose acetate, polyvinyl alcohol, unsaturated polyester, melamine resin, A phenol resin, a urea resin, a polyimide, etc. can be mentioned. In addition, various acrylic rubbers, ethylene-vinyl acetate copolymers, ethylene-acrylic acid copolymers and alkali metal salts thereof (so-called ionomers), ethylene-acrylic acid alkyl ester copolymers (for example, ethylene-ethyl acrylate copolymer) Copolymer, ethylene-butyl acrylate copolymer), diene rubber (for example, 1,4-polybutadiene, 1,2-polybutadiene, polyisoprene, polychloroprene), copolymer of diene and vinyl monomer (for example, Styrene-butadiene random copolymer, styrene-butadiene block copolymer, styrene-butadiene-styrene block copolymer, styrene-isoprene random copolymer, styrene-isoprene block copolymer, styrene-isoprene-styrene block copolymer Polymer, polybutadiene Styrene-grafted styrene, butadiene-acrylonitrile copolymer), polyisobutylene, copolymer of isobutylene and butadiene or isoprene, butyl rubber, natural rubber, thiocol rubber, polysulfide rubber, acrylic rubber, nitrile rubber, Examples include polyether rubber, epichlorohydrin rubber, fluorine rubber, silicone rubber, and other thermoplastic elastomers such as polyurethane, polyester, and polyamide.

Furthermore, those having various degrees of crosslinking, those having various microstructures, for example, those having a cis structure, a trans structure, etc., those having a vinyl group, or those having various average particle diameters (in the resin composition) Or a multi-layer polymer called a so-called core-shell rubber composed of a core layer and one or more shell layers covering the core layer, and adjacent layers made of different types of polymers can be used. A core-shell rubber containing a silicone compound can also be used.
These polymers may be used alone or in combination of two or more.

  When the resin composition of this invention contains polymers other than a cellulose derivative, about 30 mass parts or less are preferable with respect to 100 mass parts of cellulose derivatives, and about 2-10 mass parts is more preferable.

  The resin composition of the present invention may contain a plasticizer. Thereby, a flame retardance and a moldability can be improved further. As the plasticizer, those commonly used for polymer molding can be used. Examples thereof include polyester plasticizers, glycerin plasticizers, polycarboxylic acid ester plasticizers, polyalkylene glycol plasticizers, and epoxy plasticizers.

  Specific examples of the polyester plasticizer include acid components such as adipic acid, sebacic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, rosin, propylene glycol, 1,3-butanediol, 1,4 -Polyesters composed of diol components such as butanediol, 1,6-hexanediol, ethylene glycol and diethylene glycol, and polyesters composed of hydroxycarboxylic acids such as polycaprolactone. These polyesters may be end-capped with a monofunctional carboxylic acid or monofunctional alcohol, or may be end-capped with an epoxy compound or the like.

  Specific examples of the glycerin plasticizer include glycerin monoacetomonolaurate, glycerin diacetomonolaurate, glycerin monoacetomonostearate, glycerin diacetomonooleate, and glycerin monoacetomonomontanate.

Specific examples of polycarboxylic acid plasticizers include phthalates such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, diheptyl phthalate, dibenzyl phthalate, butyl benzyl phthalate, and trimellitic acid. Tributyl ester such as tributyl, trioctyl trimellitic acid, trihexyl trimellitic acid, diisodecyl adipate, n-octyl-n-decyl adipate, methyl diglycol butyl diglycol adipate, benzyl methyl diglycol adipate, adipic acid Adipic acid esters such as benzylbutyl diglycol, citrate esters such as triethyl acetylcitrate and tributyl acetylcitrate, azelaic acid esters such as di-2-ethylhexyl azelate, sebacin Dibutyl, and di-2-ethylhexyl sebacate, and the like.

  Specific examples of the polyalkylene glycol plasticizer include polyethylene glycol, polypropylene glycol, poly (ethylene oxide / propylene oxide) block and / or random copolymer, polytetramethylene glycol, ethylene oxide addition polymer of bisphenols, bisphenols And a polyalkylene glycol such as a propylene oxide addition polymer, a tetrahydrofuran addition polymer of bisphenol, or a terminal epoxy-modified compound thereof, a terminal ester-modified compound, a terminal ether-modified compound, and the like.

  The epoxy plasticizer generally refers to an epoxy triglyceride composed of an alkyl epoxy stearate and soybean oil, but there are also so-called epoxy resins mainly made of bisphenol A and epichlorohydrin. Can be used.

  Specific examples of other plasticizers include benzoic acid esters of aliphatic polyols such as neopentyl glycol dibenzoate, diethylene glycol dibenzoate, triethylene glycol di-2-ethylbutyrate, fatty acid amides such as stearamide, oleic acid Examples thereof include aliphatic carboxylic acid esters such as butyl, oxy acid esters such as methyl acetylricinoleate and butyl acetylricinoleate, pentaerythritol, and various sorbitols.

  When the resin composition of the present invention contains a plasticizer, the content is usually about 5 parts by mass or less, preferably about 0.005 to 5 parts by mass, more preferably about 100 parts by mass of the cellulose derivative. About 0.01 to 1 part by mass.

The molded article of the present invention is obtained by molding a resin composition containing the cellulose derivative of the present invention or the cellulose derivative of the present invention and an additive (preferably a filler). More specifically, the resin composition containing the cellulose derivative of the present invention or the cellulose derivative of the present invention and a filler is melted by heating or the like and molded by various molding methods.
Examples of the molding method include injection molding, extrusion molding, blow molding and the like.
The heating temperature is usually about 160 to 260 ° C, preferably about 180 to 240 ° C.

The use of the molded product of the present invention is not particularly limited. For example, components of automobiles, home appliances, electrical / electronic devices (OA / media related devices, optical devices, communication devices, etc.), mechanical components, Examples include housing and building materials.
More specifically, as automobile components, for example, door rims, pillars, instrument panels, console boxes, rocker panels, armrests, door panels, spare tire covers, sterling, shift knobs, car navigation, air conditioner outlets, meters , Various switches, safety belt parts, airbags and airbag covers, torque control levers, register blades, washer levers, window regulator handles and knobs, passing light levers, sun visors, overhead consoles, rearview mirrors, various motor housings, ETC Interior parts, etc.

Bumper, front spoiler, front grill, grill guard, fender, rocker molding, side step, door mirror cover, door mirror stay, cowl louver, wheel cap, side protector, side molding, side lower skirt, side step, roof rail, rear spoiler, rear under Exterior parts such as spoiler, garnish, pillar, wiper cover, hard spare tire cover, tailgate, back door, lamp bezel,

Air intake duct, engine cover, engine floor cover, reserve tank, radiator shroud, fan, air cleaner case, timing belt cover, cylinder head cover, oil cap, oil pan, oil filter, fuel cap, fuel strainer, vapor canister housing, under Deflector, alternator terminal, alternator connector, IC regulator, potentiometer base, various valves such as exhaust gas valves, fuel-related / exhaust / intake-related pipes, air intake nozzle snorkel, intake manifold, fuel pump, engine coolant joint, carburetor Main body, carburetor spacer, exhaust gas sensor, cooling water center -Oil temperature sensor, throttle position sensor, air flow meter, thermostat base for air conditioner, heating hot air flow control valve, brush holder for radiator motor, water pump impeller, wiper motor, distributor, starter switch, starter relay, transmission Applicable to engine peripherals and mechanical parts such as wire harness, window washer nozzle, air conditioner panel switch board, coil for fuel related electromagnetic valve, fuse connector, horn, horn terminal, lamp socket, lamp reflector, lamp housing .

  As home appliances, for example, TV (CRT, liquid crystal, plasma, organic EL) VTR, iron, hair dryer, rice cooker, microwave oven, audio / video equipment (microphone, speaker, amplifier, tuner, radio cassette), various AV discs Player, hard disk recorder, DVD recorder, MD player, memory player, voice recorder, headphones, earphones, washing machine, washing dryer, vacuum cleaner, rice cooker, refrigerator, freezer, pot, warmer, air conditioner, dishwasher, air Cleaners, lighting equipment, power tools, watches, watches, thermometers, massage machines, various health equipment, game machines (home game machines, arcade game machines, pachinko machines, slot machines, etc.), home robots, etc. It can be applied to exterior parts.

  OA / media-related devices include desktop computers, notebook computers, CRT displays, liquid crystal displays, organic EL displays, printers and copiers, fax machines, scanners, typewriters, word processors, electronic dictionaries, ink cartridges, toner cartridges, recording media ( HDD, CD, DVD, Blu-ray, FDD) drive, flash memory exterior, tape drive exterior, optical recording media and their cases, mouse, keyboard, digitizer, LCD projector, projector screen, laser pointer, electronic blackboard, hub, wireless It can be applied to interior and exterior parts such as LAN.

The optical device can be applied to interior and exterior parts such as a camera, a digital camera, a video camera, a telescope, binoculars, a microscope, an electron microscope, and an endoscope.
The communication device can be applied to fixed telephones, mobile phones, portable information terminals, housings of various communication terminals, radio antennas, TV antennas, parabolic antennas, interior / exterior parts such as GPS navigation devices, and the like.

  Other electrical and electronic devices include various gears, various cases, batteries (manganese batteries, nickel metal hydride batteries, lithium ion batteries) and their chargers, adapters (AC / DC, voltage converter), sensors, LEDs, connectors. , Sockets, resistors, relay cases, switches, coil bobbins, capacitors, variable capacitor cases, optical pickups, oscillators, various terminal boards, transformers, plugs, printed wiring boards, small motors, magnetic head bases, power modules, semiconductor devices, Liquid crystal devices, power generators, circuit boards, integrated circuit molds, optical disk substrates, disk cartridges, optical cards, IC memory cards, connectors, cable couplers, containers for transporting electronic components (IC trays, IC magazine cases, silicon wafer containers , Glass substrate storage container, and Yariatepu etc.), it can be applied hot melt binder, the electrode material for the binder, an optical element, a conductive embossed tape.

  As mechanical parts, it can be applied to gears, turntables, rotors, screws, springs, bearings, levers, key stems, cams, ratchets, rollers, pump casings, tanks, pipes, architectural forms and the like.

  As materials for housing and construction, wallpaper, pillars, curtains, chairs, carpets, tablecloths, futons, wash basins, vanities, storage shelves, toilet seats, toilet lids, paper holders, sash doors, blind curtain parts, Piping joint, curtain liner, blind, gas meter, water meter, water heater, water supply part, roof panel, outer wall, adjuster, plastic bundle, ceiling fishing gear, stairs, door, floor, handrail, vegetation net, vegetation mat, grass bag It can be applied to parts such as grass prevention nets, curing sheets, slope protection sheets, fly ash press sheets, drain sheets, water retention sheets, sludge / sludge dewatering bags, concrete formwork and the like.

  In addition to the above applications, film products such as print laminate films, heat-sensitive stencil printing films, release films, porous films, sheet materials such as container bags, credit cards, cash cards, ID cards, IC cards, etc. Card products, fishing lines, fishing nets, seaweed aquaculture nets, fishing bait bags and other fishery related parts, toy parts, fans, tegus, pipes, cleaning jigs, multi-films, tunnel films, bird protection sheets, vegetation protection Non-woven fabric, seedling pot, vegetation pile, seed string tape, germination sheet, house lining sheet, farm-bi fastener, slow-release fertilizer, root-proof sheet, garden net, insect net, young tree net, print laminate, Agricultural materials such as fertilizer bags, sample bags, sandbags, beast damage prevention nets, incentive straps, windproof nets, paper diapers, sanitary goods packaging materials, cotton swabs, towels Hygiene products such as toilet seat wipes, medical non-woven fabric (stitching part reinforcement, adhesion prevention film, prosthesis repair material), wound dressing material, wound tape bandage, sticky material base fabric, surgical suture, fracture reinforcement, medical use Medical supplies such as films, packaging films for calendars, stationery, clothing, foods, trays, blisters, knives, forks, spoons, tubes, plastic cans, pouches, containers, containers such as tanks, baskets, hot fills Containers, microwave cooking containers, cosmetic containers, wraps, foam buffers, paper laminate products, shampoo bottles, beverage bottles, cups, candy packaging, shrink labels, lid materials, envelopes with windows, fruit baskets, hand tapes , Easy peel packaging, egg pack, HDD packaging, compost bag, recording media packaging, shopping bag, electricity Containers and packaging for wrapping films such as child parts, natural fiber composites, golf tees, garbage bags, plastic bags, various nets, toothbrushes, stationery, draining nets, body towels, hand towels, tea packs, drainage filters, clear files It can be applied to interior and exterior parts such as bags, cooler boxes, kumade, hose reels, planters, hose nozzles, pen caps and gas lighters.

  The molded body of the present invention has excellent heat resistance and impact resistance, and has a low environmental impact. Therefore, among the above, it is suitably used as a component (especially a casing) for electrical and electronic equipment. it can.

  EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the scope of the present invention is not limited to the examples shown below.

<Synthesis Example 1: Synthesis of methylcellulose butanoate (P-1)>
In a 5 L three-necked flask equipped with a mechanical stirrer, thermometer, condenser, and dropping funnel, 80 g of methyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd .: methyl substitution degree 1.8), 1000 mL of methylene chloride and 1,000 mL of pyridine were weighed and stirred at room temperature. To this, 1000 mL of butyric anhydride was slowly added dropwise, and about 0.2 g of dimethylaminopyridine (DMAP) was further added and refluxed for 3 hours. After the reaction, the reaction solution was returned to room temperature and quenched by adding 200 mL of methanol under ice cooling. When the reaction solution was poured into methanol / water (10 L / 10 L) with vigorous stirring, a white solid was precipitated. The white solid was filtered off by suction filtration and washed with a large amount of water three times. The obtained white solid was vacuum-dried at 100 ° C. for 6 hours to obtain the objective cellulose derivative (P-1) (methylcellulose butanoate, substitution degree is described in Table 2) as a white powder (85.0 g). ).

<Synthesis Example 2: Synthesis of methylcellulose octanoate (P-2)>
In a 3 L three-necked flask equipped with a mechanical stirrer, thermometer, condenser, and dropping funnel, 80 g of methyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd .: methyl substitution degree 1.8) and 1500 mL of pyridine were weighed and stirred at room temperature. Under water cooling, 160 mL of n-octanoyl chloride was slowly added dropwise thereto, and the mixture was further stirred at 60 ° C. for 6 hours. After the reaction, the reaction solution was returned to room temperature and quenched by adding 200 mL of methanol under ice cooling. When the reaction solution was poured into 12 L of water with vigorous stirring, a white solid was precipitated. The white solid was filtered off by suction filtration and washed 3 times with a large amount of methanol solvent. The obtained white solid was vacuum-dried at 100 ° C. for 6 hours to obtain the objective cellulose derivative (P-2) (methylcellulose octanoate, the degree of substitution described in Table 2) as a white powder (93.3 g). ).

<Synthesis Example 3: Synthesis of methylcellulose-2-ethylhexanoate (P-3)>
The target cellulose derivative (P-3) (methylcellulose-2-ethylhexanoate, substitution degree is shown in Table 2 except that n-octanoyl chloride was changed to 2-ethylhexanoyl chloride in Synthesis Example 2. ) Was obtained as a white powder (91.4 g).

<Synthesis Example 4: Synthesis of methylcellulose-2-ethylhexanoate (P-4)>
The target cellulose derivative (P-4) (methyl cellulose) was similarly prepared except that methyl cellulose (manufactured by Wako Pure Chemical: methyl substitution degree 1.8) was changed to methyl cellulose (synthetic product: methyl substitution degree 2.1) in Synthesis Example 3. 2-ethylhexanoate, the degree of substitution described in Table 2) was obtained as a white powder (88.0 g).

<Synthesis Example 5: Synthesis of methylcellulose-2-methylheptanoate (P-5)>
The target cellulose derivative (P-5) (methylcellulose-2-methylheptanoate, substitution degree is shown in Table 2 except that 2-ethylhexanoyl chloride was changed to 2-methylheptanoyl chloride in Synthesis Example 3. As a white powder (92.0 g).

<Synthesis Example 6: Synthesis of methylcellulose-2-propylpentanoate (P-6)>
The target cellulose derivative (P-6) (methylcellulose-2-propylpentanoate, substitution degree is shown in Table 2 except that 2-ethylhexanoyl chloride was changed to 2-propylpentanoyl chloride in Synthesis Example 4. As a white powder (89.6 g).

<Synthesis Example 7: Synthesis of ethyl cellulose-3-methylbutanoate (P-7)>
In a 3 L three-necked flask equipped with a mechanical stirrer, thermometer, condenser, and dropping funnel, 80 g of ethyl cellulose (manufactured by Aldrich: ethoxy substitution degree 2.4) and 1500 mL of pyridine were weighed and stirred at room temperature. Under water cooling, 40 mL of 3-methylbutanoyl chloride was slowly added dropwise thereto, and the mixture was further stirred at 60 ° C. for 6 hours. After the reaction, the reaction solution was returned to room temperature and quenched by adding 200 mL of methanol under ice cooling. When the reaction solution was added to 12 L of water with vigorous stirring, a white solid was precipitated. The white solid was separated by suction filtration and washed three times with a large amount of methanol / water (1/1 (v / v)) solvent. The obtained white solid was vacuum-dried at 100 ° C. for 6 hours to obtain the objective cellulose derivative (P-7) (ethyl cellulose-3-methylbutanoate, the degree of substitution described in Table 2) as a white powder. (79.6 g).

<Synthesis Example 8: Synthesis of ethylcellulose-2-ethylhexanoate (P-8)>
The target cellulose derivative (P-8) (ethylcellulose-2-yl ester) was similarly prepared except that 3-methylbutanoyl chloride was changed to 2-ethylhexanoyl chloride in Synthesis Example 7.
Ethyl hexanoate, the degree of substitution described in Table 2, was obtained as a white powder (88.5 g).

<Synthesis of Comparative Compound 1: Synthesis of 2-ethylhexanoyl cellulose (H-1)>
50 g of cellulose (manufactured by Nippon Paper Industries Co., Ltd .: KC Flock W100) and 1800 mL of dimethylacetamide were weighed in a 3 L three-necked flask equipped with a mechanical stirrer, thermometer, condenser, and dropping funnel and stirred at 120 ° C. for 2 hours. Next, 150 g of lithium chloride was added, and the mixture was further stirred for 1 hour. After returning the reaction solution to room temperature, 150 g of 2-ethylhexanoyl chloride was added dropwise at room temperature, and the mixture was further stirred at 90 ° C. for 2 hours. When the reaction solution was added to 10 L of methanol with vigorous stirring, a white solid was precipitated. The white solid was filtered off by suction filtration and washed with a large amount of methanol three times. The obtained white solid was vacuum-dried at 100 ° C. for 6 hours to obtain the desired cellulose derivative (H-1) (2-ethylhexanoyl cellulose, substitution degree of 2-ethylhexanoyl 2.1) as a white powder. (92.1 g).

<Synthesis of Comparative Compound 2: Synthesis of Methylcellulose (H-2)>
In a 3 L three-necked flask equipped with a mechanical stirrer, thermometer, condenser, and dropping funnel, 100 g of methylcellulose (Wako Pure Chemical Industries, Ltd .: methyl substitution degree 1.8) and 2000 mL of dimethylacetamide were weighed and stirred at room temperature. 100 g of powdered sodium hydroxide was added thereto and stirred at 60 ° C. for 1 hour, and then the reaction solution was cooled, 80 mL of methyl iodide was added dropwise under water cooling, and the mixture was stirred at 50 ° C. for 3 hours. When the reaction solution was added to 12 L of methanol with vigorous stirring, a white solid was precipitated. The white solid was filtered off by suction filtration and washed three times with a large amount of isopropanol. The obtained white solid was vacuum-dried at 100 ° C. for 6 hours to obtain the objective cellulose derivative (H-2) (methyl cellulose, methyl substitution degree 2.1) as a white powder (85.3 g).

Note that the compound obtained above, a hydroxyl group ^(R 2, ^{R 3} and ^{R 6)} kinds of substituted functional groups contained in the cellulose, and _DS A, DS _B and DS _C is, Cellulose Communication 6,73 This was observed and determined by ¹ H-NMR or ¹³ C-NMR using the methods described in -79 (1999) and Chrality 12 (9), 670-674.

<Measurement of physical properties of cellulose derivative>
Table 1 shows the number average molecular weight (Mn), weight average molecular weight (Mw), molecular weight distribution (MWD), glass transition temperature (Tg), and melt flow rate (MFR) at 200 ° C. for the obtained cellulose derivative. These measuring methods are as follows.
[Molecular weight and molecular weight distribution]
The number average molecular weight (Mn), the weight average molecular weight (Mw), and the molecular weight distribution (MWD) were measured using gel permeation chromatography (GPC). Specifically, tetrahydrofuran was used as a solvent, polystyrene gel was used, and the molecular weight was determined using a conversion molecular weight calibration curve obtained in advance from the constituent curve of standard monodisperse polystyrene. As the GPC apparatus, HLC-8220 GPC (manufactured by Tosoh Corporation) was used.
[Glass transition temperature (Tg)]
Using a differential scanning calorimeter (product number: DSC6200, manufactured by Seiko Electronics Co., Ltd.), the temperature was raised at 10 ° C./min and measured. In the table, “−” indicates that thermoplasticity was not exhibited.
[Melt flow rate]
In accordance with ISO1133, the measurement was performed with a load of 2 kg in a MELTINDEXER (manufactured by Toyo Seiki Seisakusho Co., Ltd.).

<Example 1: Production of molded body made of cellulose derivative>
[Test specimen preparation]
The cellulose derivative (P-1) obtained above is supplied to an injection molding machine (Imoto Seisakusho, semi-automatic injection molding machine), cylinder temperature 190 ° C., mold temperature 30 ° C., injection pressure 1.5 kgf / Multipurpose test piece of 4 × 10 × 80 mm at cm ² (impact test piece and heat deformation test piece)
Was molded.
The cylinder temperature in the polymer molding was set to a temperature at which the melt flow rate was in the range of 6 to 9 g / 10 min. The mold temperature was 30 ° C.

<Examples 2-8, Comparative Examples 1-4>
In the same manner as in Example 1, cellulose derivatives (P-2) to (P-8), and cellulose derivatives (H-1), (H-2), and (H-3) as comparative compounds (Wako Pure Chemical Industries, Ltd .: Test pieces were prepared by molding according to the molding conditions shown in Table 2 using methyl cellulose, methyl substitution degree 1.8) and (H-4) (manufactured by Aldrich: ethyl cellulose, ethyl substitution degree 2.4).

<Measurement of physical properties of test piece>
About the obtained test piece, Charpy impact strength and heat distortion temperature (HDT) were measured according to the following method. The results are shown in Table 2.
[Charpy impact strength]
In accordance with ISO 179, a notch having an incident angle of 45 ± 0.5 ° and a tip of 0.25 ± 0.05 mm is formed on a test piece molded by injection molding, 23 ° C. ± 2 ° C., 50% ± 5% RH Then, the impact strength was measured edgewise with a Charpy impact tester (manufactured by Toyo Seiki Seisakusho).
[Heat deformation temperature (HDT)]
In accordance with ISO75, a constant bending load (1.8 MPa) is applied to the center of the test piece (in the flatwise direction), the temperature is increased at a constant speed, and the temperature when the strain at the center reaches 0.34 mm is set. It was measured.

As is apparent from the results in Table 2, methylcellulose does not exhibit thermoplasticity, but by modifying the aliphatic acyl group, thermoplasticity is imparted and molding becomes possible, and high impact resistance and heat resistance. It can be seen that is expressed. In addition, in ethyl cellulose having thermoplasticity, a significant improvement in impact resistance can be seen particularly by modifying the aliphatic acyl group. Furthermore, compared with the case where 2-ethylhexanoyl cellulose is used (Comparative Example 1), the molded article using the cellulose derivative of the present invention has both high heat resistance and high impact resistance. I understand.
That is, according to the cellulose derivative of the present invention, it can be seen that an unexpected effect of achieving both the development of thermoplasticity, impact resistance and heat resistance can be obtained.

Claims (9)

  A cellulose derivative in which at least part of hydrogen atoms of a hydroxyl group contained in cellulose is substituted with a hydrocarbon group having 1 to 7 carbon atoms and an aliphatic acyl group having 4 to 11 carbon atoms.   The cellulose derivative according to claim 1, wherein the aliphatic acyl group has a branched structure.   The cellulose derivative according to claim 1 or 2, wherein the aliphatic acyl group has 7 to 9 carbon atoms.   The cellulose derivative according to claim 1, wherein the hydrocarbon group is a methyl group or an ethyl group.   The cellulose derivative according to claim 1, wherein the hydrocarbon group is a methyl group.   The resin composition containing the cellulose derivative in any one of Claims 1-5.   The molded object obtained by shape | molding the cellulose derivative in any one of Claims 1-5, or the resin composition of Claim 6.   A casing for an electric / electronic device comprising the molded article according to claim 7.   It is a manufacturing method of the cellulose derivative in any one of Claims 1-5, Comprising: The manufacturing method of a cellulose derivative including the process of making an acid chloride or an acid anhydride react with cellulose ether in the presence of a base.